Locking device for door chains

ABSTRACT

The locking device consists of two parts: (1) A shaft 2 to 3 inches long and one-eighth inches to five-thirtyseconds inches in diameter, having notches along the length of the shaft, and a large head on one end of the shaft, about 1- 1/2 inches in diameter, and (2) a cylindrical collar about 1 inch in diameter which fits over the shaft and locks in place with a thumb screw.

United States Patent [191 McGann, Jr.

LOCKING DEVICE FOR DOOR CHAINS Inventor: John J. McGann, Jr., PO. Box 991,

New Smyrna Beach, Fla. 32069 Filed: May 29, 1973 Appl. No.: 365,397

U.S. C1. 292/264, 292/288 Int. Cl. E050 19/18 Field of Search 292/258, 264, 288, 276, 292/291, 294, 307; 24/105; 85/33, 155; 151/24; 70/93, 18, 58

References Cited UNITED STATES PATENTS Rhines 151/24 Nov. 19, 1974 Down 24/105 Abella et a1. .L 292/276 X Kaden 292/264 Lewgowd 292/276 X Primary Examinei-Richard E. Moore ABSTRACT The locking device consists of two parts: l) A shaft 2 to 3 inches long and one-eighth inches to fivethirtyseconds inches in diameter, having notches along the length of the shaft, and a large head on one end of the shaft, about l- /z'inches in diameter, and (2) a cylindrical collar about 1 inch in diameter which fits over the shaft and locks in place with a thumb screw.

3 Claims, 4 Drawing Figures LOCKING DEVICE FOR DOOR CHAINS This invention relates to locking devices for door chains. The object of this invention is to provide a simple, inexpensive means of securely locking a door chain in place so that it cannot be removed from the outside.

Burglars can pick most locks and can remove the door chain from the slot from outside the door. Various methods have been developed to prevent removal of the chain, such as installing a lock at one end of the chain.

It is the object of this invention to provide a simple, inexpensive device which can be easily installed and removed, and will prevent removal of the chain by someone outside the door. A very important feature of this device is that it is designed so that it can be used as an advertising give-away item. There is room on the large head of the device to print the name of the company which gives the item away, and other advertising information. Another important feature of this invention is that it can be removed very quickly in case of fire by a few turns of the thumb screw and by sliding the collar off the shaft.

Briefly, the invention consists of two parts a screwlike device with a large head, and notches along the shaft, and a collar equipped with a thumb screw.

FIG. 1 is a side view of the shaft, and shows the large head, the notches along the shaft, the collar slipped onto the shaft, and the thumbscrew tightened in place.

FIG. 2 is a top view of the head of the shaft, showing an example of the printing of the name of a company FIG. 4 is a view of the invention installed in adoor chain.

The locking device shortens the chain and prevents the chain from being removed from the slot, until the locking device is removed. The door chain with locking device in place prevents the opening of the door.

What is claimed is:

l. A locking device, secured through selected links of a door chain, and consisting of two parts: l a screwlike device, consisting of a large head, and a shaft hav ing notches along the length'of the shaft, and (2) a cylindrical collar which fits on the shaft, and having a thumb screw which screws into threads tapped into the cylindrical collar, and into the notches on the shaft.

2. A locking device, as defined in claim 1 which has space on the large head for advertising, and is suitable for an advertising handout.

3. A locking device as defined in claim 1, which can be removed from the chain quickly in case of tire.

* l =l l 

1. A locking device, secured through selected links of a door chain, and consisting of two parts: (1) a screw-like device, consisting of a large head, and a shaft having notches along the length of the shaft, and (2) a cylindrical collar which fits on the shaft, and having a thumb screw which screws into threads tapped into the cylindrical collar, and into the notches on the shaft.
 2. A locking device, as defined in claim 1 which has space on the large head for advertising, and is suitable for an advertising handout.
 3. A locking device as defined in claim 1, which can be removed from the chain quickly in case of fire. 